在此页

• 构造函数
• 实例特性
• 实例方法
• 范例
• 规范
• 浏览器兼容性
• 另请参阅
• 相关话题

WebAssembly.Table() object is a JavaScript wrapper object — an array-like structure representing a WebAssembly Table, which stores function references. A table created by JavaScript or in WebAssembly code will be accessible and mutable from both JavaScript and WebAssembly.

注意 : Tables can currently only store function references, but this will likely be expanded in the future.

构造函数

WebAssembly.Table()

创建新的 Table 对象。

实例特性

Table.prototype.length

Returns the length of the table, i.e. the number of elements.

实例方法

Table.prototype.get()

Accessor function — gets the element stored at a given index.

Table.prototype.grow()

Increases the size of the Table instance by a specified number of elements.

Table.prototype.set()

Sets an element stored at a given index to a given value.

范例

Creating a new WebAssembly Table instance

The following example (see table2.html source code and live version ) creates a new WebAssembly Table instance with an initial size of 2 elements. We then print out the table length and contents of the two indexes (retrieved via Table.prototype.get() to show that the length is two and both elements are null .

var tbl = new WebAssembly.Table({initial:2, element:"anyfunc"});
console.log(tbl.length);  // "2"
console.log(tbl.get(0));  // "null"
console.log(tbl.get(1));  // "null"
					

We then create an import object that contains the table:

var importObj = {
  js: {
    tbl:tbl
  }
};
					

Finally, we load and instantiate a wasm module (table2.wasm) using the WebAssembly.instantiateStreaming() method.  The table2.wasm module contains two functions (one that returns 42 and another that returns 83) and stores both into elements 0 and 1 of the imported table (see text representation ).  So after instantiation, the table still has length 2, but the elements now contain callable Exported WebAssembly Functions which we can call from JS.

WebAssembly.instantiateStreaming(fetch('table2.wasm'), importObject)
.then(function(obj) {
  console.log(tbl.length);
  console.log(tbl.get(0)());
  console.log(tbl.get(1)());
});
					

Note how you've got to include a second function invocation operator at the end of the accessor to actually invoke the referenced function and log the value stored inside it (e.g. get(0)() 而不是 get(0) ).

This example shows that we're creating and accessing the table from JavaScript, but the same table is visible and callable inside the wasm instance too.

规范

规范
WebAssembly JavaScript 接口 The definition of 'Table' in that specification.

浏览器兼容性

The compatibility table on this page is generated from structured data. If you'd like to contribute to the data, please check out https://github.com/mdn/browser-compat-data and send us a pull request. 更新 GitHub 上的兼容性数据

	Desktop						Mobile						Server
	Chrome	Edge	Firefox	Internet Explorer	Opera	Safari	Android webview	Chrome for Android	Firefox for Android	Opera for Android	Safari on iOS	Samsung Internet	Node.js
Table	Chrome 57	Edge 16	Firefox 52 52 Disabled in the Firefox 52 Extended Support Release (ESR).	IE No	Opera 44	Safari 11	WebView Android 57	Chrome Android 57	Firefox Android 52 52 Disabled in the Firefox 52 Extended Support Release (ESR).	Opera Android 43	Safari iOS 11	Samsung Internet Android 7.0	nodejs 8.0.0
Table() 构造函数	Chrome 57	Edge 16	Firefox 52 52 Disabled in the Firefox 52 Extended Support Release (ESR).	IE No	Opera 44	Safari 11	WebView Android 57	Chrome Android 57	Firefox Android 52 52 Disabled in the Firefox 52 Extended Support Release (ESR).	Opera Android 43	Safari iOS 11	Samsung Internet Android 7.0	nodejs 8.0.0
get	Chrome 57	Edge 16	Firefox 52 52 Disabled in the Firefox 52 Extended Support Release (ESR).	IE No	Opera 44	Safari 11	WebView Android 57	Chrome Android 57	Firefox Android 52 52 Disabled in the Firefox 52 Extended Support Release (ESR).	Opera Android 43	Safari iOS 11	Samsung Internet Android 7.0	nodejs 8.0.0
grow	Chrome 57	Edge 16	Firefox 52 52 Disabled in the Firefox 52 Extended Support Release (ESR).	IE No	Opera 44	Safari 11	WebView Android 57	Chrome Android 57	Firefox Android 52 52 Disabled in the Firefox 52 Extended Support Release (ESR).	Opera Android 43	Safari iOS 11	Samsung Internet Android 7.0	nodejs 8.0.0
length	Chrome 57	Edge 16	Firefox 52 52 Disabled in the Firefox 52 Extended Support Release (ESR).	IE No	Opera 44	Safari 11	WebView Android 57	Chrome Android 57	Firefox Android 52 52 Disabled in the Firefox 52 Extended Support Release (ESR).	Opera Android 43	Safari iOS 11	Samsung Internet Android 7.0	nodejs 8.0.0
set	Chrome 57	Edge 16	Firefox 52 52 Disabled in the Firefox 52 Extended Support Release (ESR).	IE No	Opera 44	Safari 11	WebView Android 57	Chrome Android 57	Firefox Android 52 52 Disabled in the Firefox 52 Extended Support Release (ESR).	Opera Android 43	Safari iOS 11	Samsung Internet Android 7.0	nodejs 8.0.0

图例

完整支持

完整支持

不支持

不支持

见实现注意事项。

另请参阅

• WebAssembly 概述页面
• WebAssembly 概念
• 使用 WebAssembly JavaScript API

元数据

• 最后修改： May 8, 2020

相关话题

1. 标准内置对象
2. WebAssembly
3. 方法
   1. WebAssembly.compile()
   2. WebAssembly.compileStreaming()
   3. WebAssembly.instantiate()
   4. WebAssembly.instantiateStreaming()
   5. WebAssembly.validate()
4. 相关页面：
5. WebAssembly.Module
6. WebAssembly.Global
7. WebAssembly.Instance
8. WebAssembly.Memory
9. WebAssembly.Table
10. WebAssembly.CompileError
11. WebAssembly.LinkError
12. WebAssembly.RuntimeError
13. 继承：
14. Object
15. 特性
    1. Object.prototype.__proto__
    2. Object.prototype.constructor
16. 方法
    1. Object.prototype.__defineGetter__()
    2. Object.prototype.__defineSetter__()
    3. Object.prototype.__lookupGetter__()
    4. Object.prototype.__lookupSetter__()
    5. Object.prototype.hasOwnProperty()
    6. Object.prototype.isPrototypeOf()
    7. Object.prototype.propertyIsEnumerable()
    8. Object.prototype.toLocaleString()
    9. Object.prototype.toSource()
    10. Object.prototype.toString()
    11. Object.prototype.valueOf()
    12. Object.setPrototypeOf()